Semiconductor device

ABSTRACT

A semiconductor device includes: an interface chip including a read timing control circuit that outputs, in response to a command signal and a clock signal supplied from the outside, a plurality of read control signals that are each in synchronization with the clock signal and have different timings; and core chips including a plurality of internal circuits that are stacked on the interface chip and each perform an operation indicated by the command signal in synchronization with the read control signals. According to the present invention, it is unnecessary to control latency in the core chips and therefore to supply the clock signal to the core chips.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a semiconductor device, andparticularly to a semiconductor device in which a front-end portionhaving an interface function and a back-end portion containing a memorycore are integrated onto separate semiconductor chips.

2. Description of Related Art

A storage capacity required for a semiconductor memory device, such asDRAM (Dynamic Random Access Memory), has been growing over years. Tomeet the requirement, in recent years, a memory device called multichippackage, in which a plurality of memory chips is stacked, has beenproposed. However, memory chips used in the multichip package aretypical, stand-alone memory chips. Therefore, the memory chips eachcontain a front-end portion that provides an interface with an externalsection (which is for example a memory controller). Accordingly, anoccupied space that can be allocated to a memory core in each memorychip is limited to an area that is calculated by subtracting theoccupied space of the front-end portion from the total area of the chip.Therefore, it is difficult to dramatically increase the storage capacityper chip (or per memory chip).

Another problem is that even though a circuit that makes up thefront-end portion is a logic circuit, the back-end portion containing amemory core is produced at the same time as the front-end portion,making it difficult to speed up a transistor of the front-end portion.

The following method is proposed as a solution to the problems that afront-end portion and a back-end portion are integrated onto separatechips, and the chips are stacked in order to make one semiconductormemory device (see Japanese Patent Application Laid-Open No.2007-158237). According to the method, on a core chip where the back-endportion is integrated, an occupied space that can be allocated to amemory core increases. Therefore, it is possible to increase the storagecapacity per chip (or per core chip). Meanwhile, an interface chip wherethe front-end portion is integrated can be produced in a differentprocess from that of the memory core. Therefore, it is possible to forma circuit using a high-speed transistor. Moreover, a plurality of corechips can be allocated to one interface chip. Thus, it is possible toprovide an extremely large-capacity, high-speed semiconductor memorydevice as a whole.

In a semiconductor device such as DRAM, an internal control signal isgenerated by decoding a command issued from an external controller. Onthe basis of the internal control signal, various operations, which forexample include activation of a word line, column switch or dataamplifier and the like, are performed. The timings of the operations arecontrolled with the use of a clock signal. Accordingly, various circuitblocks are each activated at the most appropriate timings. In oneexample, when a read command is issued, a column switch is thenactivated at a predetermined timing. After that, a data amplifier isactivated at a predetermined timing. As a result, read data are read outfrom a memory cell array.

In recent years, for a DRAM, a Posted CAS method has been employed sothat a column-related command, such as read command, is issued prior toan original issuing timing. In a DRAM that uses the Posted CAS method,after a column-related command, such as read command, is issued, aninternal control signal is latched in a chip. After being delayed by aperiod of additive latency (AL), the internal control signal is suppliedto various circuit blocks. Such latency control has been performed evenin each memory chip of a stacked semiconductor device (see JapanesePatent Application Laid-Open No. 2006-277870).

However, in order for latency control to be performed in each memorychip of a stacked semiconductor device, each memory chip needs to beprovided with a latency counter that counts the latency. Therefore, theproblem is that the chip area of a memory chip increases.

Moreover, a clock signal needs to be supplied to each memory chip tooperate the latency counter. The clock signal is very short in signalwidth compared with various internal control signals. Therefore, forexample, when the clock signal is commonly supplied from an interfacechip to a plurality of core chips, parasitic capacitance components andparasitic resistance components of a clock line could distort thewaveform, possibly making it difficult to count the latency.

In particular, as in the semiconductor device disclosed in JapanesePatent Application Laid-Open No. 2007-158237, in a semiconductor deviceof a type that transmits a signal using a through silicon via, aparasitic capacitance component of the through silicon via is relativelylarge. As a result, the above problems become more serious. Even when aresistance value of the through silicon via is higher than a designvalue for some reason, the above problems become more serious.

SUMMARY

In one embodiment, there is provided a semiconductor device thatincludes: a first chip including a timing control circuit that outputs,in response to a first command signal and a clock signal supplied fromoutside, a plurality of second command signals having different timingsfrom each other in synchronization with the clock signal; and a secondchip stacked on the first chip including a plurality of internalcircuits, each of the internal circuits performing an operationindicated by the first command signal in synchronization withcorresponding one of the second command signals.

In another embodiment, there is provided a semiconductor device thatincludes: an interface chip to which an address signal and a firstcommand signal are supplied from outside; and a plurality of core chipsto which different chip addresses are assigned, respectively, whereinthe interface chip includes a first command delay circuit generating asecond command signal by delaying the first command signal, and a firstchip address delay circuit generating a second chip address by delayinga first chip address, the interface chip commonly supplying the secondcommand signal and the second chip address to the core chips, and eachof the core chips includes a first judgment circuit activating a firstmatching signal when the second chip address matches a chip addressassigned to the core chips, and a first internal circuit performing anoperation in synchronization with the second command signal when thefirst matching signal is activated.

According to the present invention, in the first chip (interface chip)that receives the first command signal, the first command signal isdelayed to generate the second command signal. The generated secondcommand signal is supplied to the second chip (core chip). Therefore,there is no need to provide a circuit that delays the first commandsignal in the second chip. Accordingly, it is unnecessary to supply theclock signal from the first chip to the second chip. Therefore,particularly in a semiconductor device of a type that uses a throughsilicon via to interconnect a plurality of chips, it is possible tosolve the above problems.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present inventionwill be more apparent from the following description of certainpreferred embodiments taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a schematic cross-sectional view provided to explain thestructure of a semiconductor device 10 according to the preferredembodiment of the present invention;

FIGS. 2A to 2C are diagrams showing the various types of through siliconvia TSV provided in a core chip;

FIG. 3 is a cross-sectional view illustrating the structure of thethrough silicon via TSV of the type shown in FIG. 2A;

FIG. 4 is a schematic view for describing an address allocation in LRA-1system;

FIG. 5 is a schematic view for describing an address allocation in LRA-2system;

FIG. 6 is a schematic view for describing an address allocation in LRA-3system;

FIG. 7 is a schematic view for describing an address allocation in PRAsystem;

FIG. 8 is a block diagram showing a configuration of an interface chipIF;

FIG. 9 is a block diagram showing a configuration of core chips CC0 toCC7;

FIG. 10 is a circuit diagram showing a read control circuit 100;

FIG. 11 is a circuit diagram showing a write control circuit 200;

FIG. 12 is a circuit diagram showing an auto-precharge control circuit300;

FIG. 13 is a timing chart illustrating a read operation;

FIG. 14 is a timing chart illustrating a write operation;

FIG. 15 is a timing chart illustrating an auto-precharge operation;

FIG. 16 is a block diagram showing a modified example;

FIG. 17 is a block diagram showing another modified example; and

FIG. 18 is a block diagram showing a chip address generation circuit400.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Preferred embodiments of the present invention will be explained belowin detail with reference to the accompanying drawings.

FIG. 1 is a schematic cross-sectional view provided to explain thestructure of a semiconductor device 10 according to the preferredembodiment of the present invention.

As shown in FIG. 1, the semiconductor device 10 according to thisembodiment has the structure where 8 core chips CC0 to CC7 that have thesame function and structure and are manufactured using the samemanufacture mask, an interface chip IF that is manufactured using amanufacture mask different from that of the core chips CC0 to CC7 and aninterposer IP are laminated. The core chips CC0 to CC7 and the interfacechip IF are semiconductor chips using a silicon substrate and areelectrically connected to adjacent chips in a vertical direction throughplural Through Silicon Vias (TSV) penetrating the silicon substrate. Thethrough silicon via may be referred to as a penetration electrode.Meanwhile, the interposer IP is a circuit board that is made of a resin,and plural external terminals (solder balls) SB are formed in a backsurface IPb of the interposer IP.

The core chips CC0 to CC7 are semiconductor chips from which a so-calledfront-end portion, which performs an interface with an outside, ofcircuit blocks included in a normal stand-alone SDRAM (SynchronousDynamic Random Access Memory), is removed. That is, each of the corechips CC0 to CC7 is a semiconductor chip where only the circuit blocksbelonging to the back end unit are integrated in principle. As thecircuit blocks that are included in the front end unit, aparallel-serial converting circuit that performs parallel/serialconversion on input/output data between a memory cell array and a datainput/output terminal and a DLL (Delay Locked Loop) circuit thatcontrols input/output timing of data are exemplified, which will bedescribed in detail below.

On the other hand, the interface chip IF is a semiconductor chip onwhich only the front-end portion of the circuit blocks included in thenormal stand-alone SDRAM is integrated. The interface chip IF functionsas a front-end portion common to 8 core chips CC0 to CC7. Accordingly,all of the external accesses are made through the interface chip IF, anddata input and data output are made through the interface chip IF.

The interface chip IF functions as a common front end unit for the eightcore chips CC0 to CC7. Accordingly, all external accesses are performedthrough the interface chip IF and inputs/outputs of data are alsoperformed through the interface chip IF. In this embodiment, theinterface chip IF is disposed between the interposer IP and the corechips CC0 to CC7. However, the position of the interface chip IF is notrestricted in particular, and the interface chip IF may be disposed onthe core chips CC0 to CC7 and may be disposed on the back surface IPb ofthe interposer IP. When the interface chip IF is disposed on the corechips CC0 to CC7 in a face-down manner or is disposed on the backsurface IPb of the interposer IP in a face-up manner, the throughsilicon via TSV does not need to be provided in the interface chip IF.The interface chip IF may be disposed to be interposed between the twointerposers IP.

The interposer IP functions as a rewiring substrate to increase anelectrode pitch and secures mechanical strength of the semiconductordevice 10. That is, an electrode 91 that is formed on a top surface IPaof the interposer IP is drawn to the back surface IPb via a through-holeelectrode 92 and the pitch of the external terminals SB is enlarged bythe rewiring layer 93 provided on the back surface IPb. In FIG. 1, onlythe two external terminals SB are shown. In actuality, however, three ormore external terminals are provided. The layout of the externalterminals SB is the same as that of the DDR3-type SDRAM that isdetermined by the regulation. Accordingly, the semiconductor memorydevice can be treated as one DDR3-type SDRAM from the externalcontroller.

As shown in FIG. 1, a top surface of the uppermost core chip CC0 iscovered by an NCF (Non-Conductive Film) 94 and a lead frame 95. Gapsbetween the core chips CC0 to CC7 and the interface chip IF are filledwith an underfill 96 and surrounding portions of the gaps are covered bya sealing resin 97. Thereby, the individual chips are physicallyprotected.

When most of the through silicon vias TSV provided in the core chips CC0to CC7 are two-dimensionally viewed from a lamination direction, thatis, viewed from an arrow A shown in FIG. 1, the through silicon vias TSVare short-circuited from the through silicon vias TSV of other layersprovided at the same position. That is, as shown in FIG. 2A, thevertically disposed through silicon vias TSV1 that are provided at thesame position in plain view are short-circuited, and one wiring line isconfigured by the through silicon via TSV1. The through silicon via TSV1that are provided in the core chips CC0 to CC7 are connected to internalcircuits 4 in the core chips, respectively. Accordingly, input signals(command signal, address signal, etc.) that are supplied from theinterface chip IF to the through silicon vias TSV1 shown in FIG. 2A arecommonly input to the internal circuits 4 of the core chips CC0 to CC7.Output signals (data etc.) that are supplied from the core chips CC0 toCC7 to the through silicon via TSV1 are wired-ORed and input to theinterface chip IF.

Meanwhile, as shown in FIG. 2B, the apart of the through silicon viasTSV are not directly connected to the through silicon via TSV2 of otherlayers provided at the same position in plain view but are connected tothe through silicon via TSV2 of other layers through the internalcircuits 5 provided in the core chips CC0 to CC7. That is, the internalcircuits that are provided in the core chips CC0 to CC7 arecascade-connected through the through silicon via TSV2. This kind ofthrough silicon via TSV2 is used to sequentially transmit predeterminedinformation to the internal circuits 5 provided in the core chips CC0 toCC7. As this information, layer address information to be describedbelow is exemplified.

Another part of the through silicon vias TSV is short-circuited from thethrough silicon vias TSV of other layer provided at the differentposition in plan view, as shown in FIG. 2C. With respect to this kind ofthrough silicon vias TSV group 3, internal circuits 6 of the core chipsCC0 to CC7 are connected to the through silicon via TSV3 a provided atthe predetermined position P in plain view. Thereby, information can beselectively input to the internal circuits 6 provided in the core chips.As this information, defective chip information to be described below isexemplified.

As such, as types of the through silicon vias TSV provided in the corechips CC0 to CC7, three types (TSV1 to TSV3) shown in FIGS. 2A to 2Cexist. As described above, most of the through silicon vias TSV are of atype shown in FIG. 2A, and an address signal and a command signal, andthe like are supplied from the interface chip IF to the core chips CC0to CC7, through the through silicon via TSV1 of the type shown in FIG.2A. Read data and write data are input to and output from the interfacechip IF through the through silicon via TSV1 of the type shown in FIG.2A. Meanwhile, the through silicon vias TSV2 and TSV3 of the types shownin FIGS. 2B and 2C are used to provide individual information to thecore chips CC0 to CC7 having the same structure.

FIG. 3 is a cross-sectional view illustrating the structure of thethrough silicon via TSV1 of the type shown in FIG. 2A.

As shown in FIG. 3, the through silicon via TSV1 is provided topenetrate a silicon substrate 80 and an interlayer insulating film 81provided on a surface of the silicon substrate 80. Around the throughsilicon via TSV1, an insulating ring 82 is provided. Thereby, thethrough silicon via TSV1 and a transistor region are insulated from eachother. In an example shown in FIG. 3, the insulating ring 82 is provideddouble. Thereby, capacitance between the through silicon via TSV1 andthe silicon substrate 80 is reduced.

An end 83 of the through silicon via TSV1 at the back surface of thesilicon substrate 80 is covered by a back surface bump 84. The backsurface bump 84 is an electrode that contacts a surface bump 85 providedin a core chip of a lower layer. The surface bump 85 is connected to anend 86 of the through silicon via TSV1, through plural pads P0 to P3provided in wiring layers L0 to L3 and plural through-hole electrodesTH1 to TH3 connecting the pads to each other. Thereby, the surface bump85 and the back surface bump 84 that are provided at the same positionin plain view are short-circuited. Connection with internal circuits(not shown in the drawings) is performed through internal wiring lines(not shown in the drawings) drawn from the pads P0 to P3 provided in thewiring layers L0 to L3.

Before detailed circuit structures of the interface chip IF and the corechips CC0 to CC7 are described, an address allocation in a semiconductordevice 10 according to the present embodiment will be described.

The semiconductor device 10 according to the present embodiment canchange the address allocation by a mode selection. There are roughlyprepared an LRA (Logical Rank Address) system and a PRA (Physical RankAddress) system in the semiconductor device 10. The LRA system is anaddress allocation system in which plural banks mounted to the differentcore chips CC0 to CC7, respectively, are handled as one bank by acontroller. On the other hand, the PRA system is an address allocationsystem in which each of the plural banks mounted to the respective corechips CC0 to CC7 is handled as one bank. In the present embodiment,there are three types in the LRA system. Each of three types is referredto as LRA-1 system, LRA-2 system, and LRA-3 system, for the sake ofconvenience. The respective systems will specifically be describedbelow.

FIG. 4 is a schematic view for describing the address allocation in theLRA-1 system. In FIGS. 4 to 7, one square indicates a bank. Therefore, asingle core chip includes banks 0 to 7.

As illustrated in FIG. 4, in the LRA-1 system, any one of the core chipsCC0 to CC7 is selected based upon a part of an address signal, which isXn+2, Xn+1, and Xn (chip address), supplied during a row-access (upon anissuance of an active command ACT), and any one of banks 0 to 7 isselected based upon bank address signals BA0 to BA2 supplied during therow access and a column access. The controller recognizes 8 banks,included in the different core chips CC0 to CC7 and having the samenumber, as one bank.

In this system, the chip address is not supplied during the columnaccess (upon the issuance of a column command). However, since thecontroller recognizes 8 banks, included in the different core chips CC0to CC7 and having the same number, as one bank, the controller canidentify to which one of the core chips CC0 to CC7 the column access ismade during the column access, even if the chip address is not supplied.Because there is inevitably one core chip in which the bank designatedupon the column access is in an active state.

For example, it is supposed that the encircled banks are in the activestate in FIG. 4. If the designated bank upon the column access is thebank 0, the column access is made to the core chip CC7 in which the bank0 is in the active state. If the designated bank upon the column accessis the bank 1, the column access is made to the core chip CC5 in whichthe bank 1 is in the active state.

As described above, the selection of the core chips CC0 to CC7 is madeduring the row access in the LRA-1 system. The controller recognizes thecore chips CC0 to CC7 as one DRAM, so that a chip selection signal (CS)to be used is also 1 bit. Therefore, the number of memory cells accessedby one row access becomes 1 kilobyte, and the number of the rank becomes1.

FIG. 5 is a schematic view for describing the address allocation in theLRA-2 system.

As illustrated in FIG. 5, in the LRA-2 system, the core chips CC0 to CC3or the core chips CC4 to CC7 are selected based upon chip selectionsignals CS0 and CS1 of two bits, and any one of selected 4 core chips isselected based upon a part of an address signal, which is Xn+1, and Xn(chip address), supplied during a row-access. The bank address signalsBA0 to BA2 are supplied during both the row access and the columnaccess.

In this system, the core chips CC0 to CC3 or the core chips CC4 to CC7are selected by using the chip selection signals, so that the ranknumber viewed from the controller becomes 2. Like the LRA-1 system, theselection of the core chips CC0 to CC7 is determined during the rowaccess, so that the number of memory cells accessed by one row accessbecomes 1 kilobyte, as in the LRA-1 system. Although the chip address isnot supplied during the column access, a problem is not caused with thissituation, as in the LRA-1 system.

In this system, the core chips CC0 to CC3 and the core chips CC4 to CC7are identified by the chip selection signals CS0 and CS1. Therefore, thebanks belonging to the core chips CC0 to CC3 and the banks belonging tothe core chips CC4 to CC7 are handled as different banks by thecontroller. Accordingly, the bank 0 in the core chip CC2 and the bank 0in the core chip CC7 can be simultaneously brought into the active stateas in the example in FIG. 5.

FIG. 6 is a schematic view for describing the address allocation in theLRA-3 system.

As illustrated in FIG. 6, in the LRA-3 system, any one set of the corechips CC0 and CC2, the core chips CC1 and CC3, the core chips CC4 andCC6, and the core chips CC5 and CC7 is selected based upon a part of theaddress signals, which is Xn+2 and Xn, supplied during the row access,and either one of the selected two core chips is selected based upon apart of the address signals, which is Yn+1, supplied during the columnaccess. The bank address signals BA0 to BA2 are supplied during both therow access and the column access.

In this system, the selection of the core chips CC0 to CC7 is made basedupon the part of the address signals, which is Xn+2 and Xn, suppliedduring the row access, and a part of the address signals, which is Yn+1,supplied during the column access. Therefore, the chip address becomesXn+2, Xn, and Yn+1. Since two core chips are in the active state duringthe row access, the number of memory cells accessed by one row accessbecomes double that in the LRA-1 system and LRA-2 system. For example,it becomes 2 kilobytes. The rank number is 1, as in the LRA-1 system.

FIG. 7 is a schematic view for describing the address allocation in thePRA system.

As illustrated in FIG. 7, the PRA system is the one in which chipaddresses P2, P1, and P0, which are a part of the address signal, andthe bank address signals BA0 to BA2 are supplied during both the rowaccess and the column access. In this system, the controller recognizesall banks as different banks. Specifically, the controller recognizes 64banks in the present embodiment. Therefore, the number and thecombination of the banks, which become the active state, is optional,wherein the maximum of 64 banks can be brought into the active state.

The above description is the detail of the respective address allocationsystems. The address allocation systems can be changed by the modeselection.

The following describes the circuit configuration of the semiconductordevice 10 in detail. The following description uses an example in whichthe operation mode of the semiconductor device 10 is set to the PRAsystem.

FIGS. 8 and 9 are block diagrams showing the configuration of thesemiconductor device according to a preferred embodiment of the presentinvention. FIG. 8 shows the configuration of the interface chip IF indetail. FIG. 9 shows the configuration of the core chips CC in detail.

As shown in FIG. 8, the external terminals provided in the interposer IPinclude a clock terminal 11, a command terminal 12, address terminals 13a and 13 b, and a data input/output terminal 14. Besides the aboveterminals, there are a data strobe terminal, calibration terminal,power-supply terminal and the like, which are not shown in the diagrams.Among the above external terminals, all external terminals except thepower-supply terminal are connected to the interface chip IF, and notconnected directly to the core chips CC0 to CC7.

The clock terminal 11 is a terminal to which an external clock signal CKis supplied. The supplied external clock signal CK is supplied to aclock generation circuit 21 via an input buffer IB. The clock generationcircuit 21 generates an internal clock signal ICLK. The generatedinternal clock signal ICLK is supplied to various circuit blocks in theinterface chip IF. According to the present embodiment, the internalclock signal ICLK is not supplied to the core chips CC0 to CC7 throughthe through silicon vias TSV. The reason is that, as described below,the semiconductor device 10 of the present embodiment uses no clocksignal in the core chips CC0 to CC7, which is one important feature ofthe present invention.

The internal clock signal ICLK is supplied to a DLL circuit 22 and aclock generation circuit 23. The DLL circuit 22 generates an outputclock signal LCLK. The generated output clock signal LCLK is supplied toan output buffer circuit 24. The clock generation circuit 23 generates aread/write clock signal ICLKRW, which is used in a column operation. Theread/write clock signal ICLKRW is supplied to a read control circuit100, a write control circuit 200 and an auto-precharge control circuit300. The read control circuit 100, the write control circuit 200 and theauto-precharge control circuit 300 will be described later in detail.The read control circuit 100, the write control circuit 200 and theauto-precharge control circuit 300 may be referred to as “timing controlcircuits.”

The command terminal 12 is a terminal to which command signals,including the following signals, are supplied: a low address strobesignal /RAS, a column address strobe signal /CAS, a write enable signal/WE, a chip select signal /CS, and an on die termination signal ODT. Theabove command signals are supplied to a command decoder 31 via an inputbuffer IB. The command decoder 31 decodes command signals to generatevarious internal control signals. The internal control signals outputfrom the command decoder 31 include an active control signal IACT, whichis output in response to an active command ACT; a read control signalR0, which is output in response to a read command RD; a write controlsignal W0, which is output in response to a write command WR; and a moderegister set control signal IMRS, which is output in response to a moderegister set command MRS.

Among the above internal control signals, the active control signal IACTis latched by a latch circuit L10, the read control signal R0 by a latchcircuit L11, and the write control signal W0 by a latch circuit L12. Thelatch circuits L10 to L12 each perform a latch operation insynchronization with the internal clock signal ICLK. The internalcontrol signals latched by the latch circuits L10 to L12 are commonlysupplied to the core chips CC0 to CC7 through the through silicon viasTSV. The read control signal R0 latched by the latch circuit L11 is alsosupplied to the read control circuit 100, and the write control signalW0 latched by the latch circuit L12 to the write control circuit 200.The mode register set control signal IMRS is supplied to a mode register32.

The address terminal 13 a is a terminal to which address signals ADD (A0to A13) and bank address signals BA0 to BA2 are supplied. The suppliedaddress signals ADD and bank address signals BA0 to BA2 are supplied toa latch circuit L20 via an input buffer IB. The address terminal 13 b isa terminal to which chip addresses P0 to P2 are supplied. The suppliedchip addresses P0 to P2 are supplied to a latch circuit L21 via an inputbuffer IB. The chip addresses P0 to P2 are used to select the core chipsCC0 to CC7 when being set to a PRA mode, and correspond to high-orderbits A14 to A16 of an address signal when being set to an LRA mode. Thelatch circuits L20 and L21 both perform a latch operation insynchronization with the internal clock signal ICLK.

The addresses latched by the latch circuits L20 and L21 are commonlysupplied to the core chips CC0 to CC7 via the through silicon vias TSV,as well as to the mode register 32. Therefore, when the mode registerset control signal IMRS is being activated, the contents of the moderegister 32 are rewritten by the values of the addresses. The chipaddresses P0 to P2 latched by the latch circuit L21 are supplied even tothe read control circuit 100, the write control circuit 200 and theauto-precharge control circuit 300. The bank address signals BA0 to BA2and an address signal A10 are supplied even to the auto-prechargecontrol circuit 300. As shown in FIG. 8, the chip addresses P0 to P2latched by the latch circuit L21 are referred to as “LADD0.”

The data input/output terminal 14 is a terminal to and from which readdata DQ or write data DQ are input and output, and is connected to theoutput buffer circuit 24 and an input buffer circuit 25. The outputbuffer circuit 24 receives read data, which are supplied via aparallel/serial conversion circuit 26 and a FIFO circuit 27, and outputsthe read data to the data input/output terminal 14 in synchronizationwith the output clock signal LCLK. The input buffer circuit 25 receiveswrite data, which are supplied via the data input/output terminal 14,and supplies the write data to the parallel/serial conversion circuit26. The parallel/serial conversion circuit 26 converts parallel readdata, which are supplied from the core chips CC0 to CC7 via the throughsilicon vias TSV, into serial data. The parallel/serial conversioncircuit 26 also converts serial write data, which are supplied from theinput buffer circuit 25, into parallel data. The FIFO circuit 27receives serial read data, and supplies the serial read data to theoutput buffer circuit 24 at a desired timing under the control of a FIFOcontrol circuit 28. The FIFO control circuit 28 supplies a timing signalFIFORS to the FIFO circuit 27 so that read data are output with adesired latency.

In that manner, between the parallel/serial conversion circuit 26 andthe core chips CC0 to CC7, in principle, parallel data are input andoutput without being converted into serial data. In a typical,stand-alone SDRAM, data are input or output from or to the outside ofthe chip in a serial manner (i.e. there is one data input/outputterminal for 1DQ). On the other hand, between the core chips CC0 to CC7and the interface chip IF, data are input or output in a parallelmanner. The feature described above is an important difference betweenthe typical SDRAM and the core chips CC0 to CC7. However, it isunnecessary to input and output all pre-fetched parallel data usingdifferent through silicon vias TSV. It is also possible to reduce thenumber of through silicon vias TSV required for 1DQ by performingpartial parallel/serial conversion in the core chips CC0 to CC7. Asdescribed below, according to the present embodiment, a process oftransferring the read or write data between the interface chip IF andthe core chips CC0 to CC7 is divided into two separate stages.

FIG. 10 is a circuit diagram showing the read control circuit 100.

As shown in FIG. 10, the read control circuit 100 includes countercircuits 101 to 104, which perform a count operation in synchronizationwith the read/write clock signal ICLKRW, and latch circuits L31 to L34,which perform a latch operation in synchronization with the internalclock signal ICLK.

The counter circuit 101 counts additive latency AL. To an input node ofthe counter circuit 101, a read control signal R0 is supplied.Therefore, when the read control signal R0 is activated, the countercircuit 101 counts the additive latency AL in synchronization with theread/write clock signal ICLKRW, and then outputs a read control signalR0 a. The read control signal R0 a is latched by the latch circuit L31and then output as a read control signal R1.

The counter circuit 102 further counts the read control signal R0 a at atime when a burst length specification signal BL8 is being activated; acount value thereof is two. The burst length specification signal BL8 isa signal that is being activated when a burst length BL is eight, and issupplied from the mode register 32. When the burst length BL is anynumber other than eight (BL=4, for example), the counter circuit 102 isskipped. A read control signal R0 b output from the counter circuit 102is latched by the latch circuit L32 and output as a read control signalR2.

The counter circuits 103 and 104 are replicas of the counter circuits101 and 102. The latch circuits L33 and L34 are replicas of the latchcircuits L31 and L32. As shown in FIG. 10, to an input node of thecounter circuit 103, a chip address LADD0 (P0 to P2) is supplied.Therefore, what is output from the latch circuit L33 is a chip addressLADD1R, which is delayed by the counter circuit 103. What is output fromthe latch circuit L34 is a chip address LADD2R, which is delayed by thecounter circuits 103 and 104.

As described above, the counter circuits 103 and 104 are replicas of thecounter circuits 101 and 102, respectively. Therefore, the read controlsignal R1 and the chip address LADD1R are output at the same time.Moreover, the read control signal R2 and the chip address LADD2R areoutput at the same time. The count values of the counter circuits 101 to104 can vary according to a set value of the mode register 32.

FIG. 11 is a circuit diagram showing the write control circuit 200.

As shown in FIG. 11, the write control circuit 200 includes countercircuits 201 to 206, which perform a count operation in synchronizationwith the read/write clock signal ICLKRW, and latch circuits L41 to L44,which perform a latch operation in synchronization with the internalclock signal ICLK.

The counter circuit 201 counts additive latency AL. To an input node ofthe counter circuit 201, a write control signal W0 is supplied.Therefore, when the write control signal W0 is activated, the countercircuit 201 counts the additive latency AL in synchronization with theread/write clock signal ICLKRW, and then outputs a write control signalW0 a. The counter circuit 202 counts CAS write latency CWL. To an inputnode of the counter circuit 202, the write control signal W0 a issupplied. Therefore, when the write control signal W0 a is activated,the counter circuit 202 counts the CAS write latency CWL insynchronization with the read/write clock signal ICLKRW, and thenoutputs a write control signal W0 b. The write control signal W0 b islatched by the latch circuit L41 and then output as a write controlsignal W1.

The counter circuit 203 further counts the write control signal WOb at atime when the burst length specification signal BL8 is being activated;a count value thereof is two. Therefore, when the burst length BL is anynumber other than eight (BL=4, for example), the counter circuit 203 isskipped. A write control signal W0 c output from the counter circuit 203is latched by the latch circuit L42 and output as a write control signalW2.

The counter circuits 204 to 206 are replicas of the counter circuits 201to 203. The latch circuits L43 and L44 are replicas of the latchcircuits L41 and L42. As shown in FIG. 11, to an input node of thecounter circuit 204, a chip address LADD0 (P0 to P2) is supplied.Therefore, what is output from the latch circuit L43 is a chip addressLADD1W, which is delayed by the counter circuits 204 and 205. What isoutput from the latch circuit L44 is a chip address LADD2W, which isdelayed by the counter circuits 204 to 206.

As described above, the counter circuits 204 to 206 are replicas of thecounter circuits 201 to 203, respectively. Therefore, the write controlsignal W1 and the chip address LADD1W are output at the same time.Moreover, the write control signal W2 and the chip address LADD2W areoutput at the same time. The count values of the counter circuits 201 to206 can vary according to a set value of the mode register 32.

FIG. 12 is a circuit diagram showing the auto-precharge control circuit300.

As shown in FIG. 12, the auto-precharge control circuit 300 includes aread auto-precharge control section 310 and a write auto-prechargecontrol section 320. To the read auto-precharge control section 310 andthe write auto-precharge control section 320, outputs of latch circuitsL51 to L53 are supplied. The latch circuits L51 to L53 latch the addresssignal A10, bank address signals BA0 to BA2 and chip address LADD0,respectively, in response to the read control signal R1 or write controlsignal W1. The address signal A10 specifies whether or not there is anauto-precharge operation, and is input in synchronization with the readcommand RD or write command WR at the same time as other address signalsADD are input. When the address signal A10 is at a high level, theauto-precharge operation is performed after a read operation or writeoperation. When the address signal A10 is at a low level, theauto-precharge operation is not performed. It is necessary to issue apre-charge command after a read operation or write operation.

The read auto-precharge control section 310 includes a readauto-precharge activation circuit 311, counter circuits 312 to 314, abank address decoder 315, and a chip address output circuit 316. Theread auto-precharge activation circuit 311 receives an output of thelatch circuit L51 and the read control signal R1. When the output of thelatch circuit L51 and the read control signal R1 are both beingactivated, the read auto-precharge activation circuit 311 generates aread auto-precharge signal RAP0. The read auto-precharge signal RAP0 isdelayed by a count operation of the counter circuit 312 and then outputas a read auto-precharge signal RAP1. The read auto-precharge signalRAP1 is supplied to the bank address decoder 315 and the chip addressoutput circuit 316.

The count operation of the counter circuit 312 is performed insynchronization with the read/write clock signal ICLKRW. A count valueof the counter circuit 312 for the read/write clock signal ICLKRW isfour. The counter circuits 313 and 314 are replicas of the countercircuit 312. Therefore, count operations of the counter circuits 313 and314 are performed in synchronization with the read/write clock signalICLKRW. The count values of the counter circuits 313 and 314 are set tothe same value as that of the counter circuit 312.

As shown in FIG. 12, to the counter circuit 313, a bank address signalBA (BA0 to BA2) is supplied from the latch circuit L52. Therefore, anoutput timing of the bank address signal BA output from the countercircuit 313 is in synchronization with the read auto-precharge signalRAP1. Moreover, to the counter circuit 314, a chip address LADD0 issupplied from the latch circuit L53. Therefore, an output timing of achip address LADD3 output from the counter circuit 314 is insynchronization with the read auto-precharge signal RAP1.

The bank address decoder 315 decodes the bank address signal BA inresponse to the activation of the read auto-precharge signal RAP1. Thedecoding results, i.e. bank specification signals B0 to B7, are latchedby a latch circuit L61 in synchronization with the read/write clocksignal ICLKRW, and then output as auto-precharge signals AP0 to AP7,respectively. The chip address output circuit 316 captures the chipaddress LADD3 in response to the activation of the read auto-prechargesignal RAPT, and then outputs the chip address LADD3 as a chip addressLADD4. An output timing of the chip address LADD4 is so designed as tobe in synchronization with an output timing of the bank specificationsignals B0 to B7 by the bank address decoder 315. The chip address LADD4is latched by a latch circuit L62 in synchronization with the read/writeclock signal ICLKRW, and then output as a chip address LADD5.

According to the above configuration, when auto-precharge is specifiedat a time when the read command RD is issued (A10=H), auto-prechargesignals AP0 to AP7 are output after a count operation of the countercircuit 101, which is included in the read control circuit 100, and acount operation of the counter circuit 312, which is included in theread auto-precharge control section 310, are completed. At the sametime, a chip address LADD5 is also output.

As shown in FIG. 12, the circuit configuration of the writeauto-precharge control section 320 is similar to that of the readauto-precharge control section 310. The write auto-precharge controlsection 320 is different from the read auto-precharge control section310 in that instead of the read control signal R1, the write controlsignal W1 is supplied. Moreover, a count value of a counter circuit 322can vary according to a set value of the mode register 32. According tothe above configuration, when the write control signal W1 is activated,a write auto-precharge signal WAP0 is activated by a writeauto-precharge activation circuit 321 and then supplied to the countercircuit 322. A write auto-precharge signal WAP1 output from the countercircuit 322 is supplied to a bank address decoder 325 and a chip addressoutput circuit 326 to activate the bank address decoder 325 and the chipaddress output circuit 326. The bank address decoder 325 decodes a bankaddress signal BA output from a counter circuit 323 to generate bankspecification signals B0 to B7. The bank specification signals B0 to B7are input into the latch circuit L61. The chip address output circuit326 receives a chip address LADD3, which is output from a countercircuit 324, and then outputs the chip address LADD3 as a chip addressLADD4. The chip address LADD4 is input into the latch circuit L62.

According to the above configuration, when auto-precharge is specifiedat a time when the write command WR is issued (A10=H), auto-prechargesignals AP0 to AP7 are output after a count operation of the countercircuit 201, which is included in the write control circuit 200, and acount operation of the counter circuit 322, which is included in thewrite auto-precharge control section 320, are completed. At the sametime, a chip address LADD5 is also output.

The above has outlined the interface chip IF. The outputs of the readcontrol circuit 100, write control circuit 200 and auto-prechargecontrol circuit 300 described above are supplied to the core chips CC0to CC7 via the through silicon vias TSV as shown in FIG. 8. The same istrue for address signals. Incidentally, the through silicon vias shownin FIG. 8 are through silicon vias TSV1 of a type shown in FIG. 2A.Therefore, a signal output from the interface chip IF via the throughsilicon vias TSV1 is commonly supplied to all the core chips CC0 to CC7.The following describes the circuit configuration of the core chips CC0to CC7.

FIG. 9 is a circuit diagram showing the core chip CC0. The core chipsCC0 to CC7 have the same circuit configuration. Therefore, in FIG. 9,only the configuration of the core chip CC0 is shown on behalf of theother core chips.

As shown in FIG. 9, a memory cell array 50, which is included in thecore chip CC0, is divided into eight banks. Incidentally, banks areunits that can accept commands separately. In other words, the banks caneach operate non-exclusively and independently of each other. In thememory cell array 50, a plurality of word lines WL and a plurality ofbit lines BIL cross each other. At the points where the word lines WLand the bit lines BIL cross each other, memory cells MC are disposed (Inthe case of FIG. 9, only one word line WL, one bit line BIL and onememory cell MC are shown). A word line WL is selected by a row decoder61. The selected word line WL is driven by a word driver 51. Moreover,the bit lines BIL are connected to corresponding sense amplifiers in asense circuit 53. A sense amplifier is selected by a column decoder 62.A column switch 52 connects the selected sense amplifier to a dataamplifier 70.

To the row decoder 61, a row address RA is supplied via a row addresslatch circuit 63. The row address latch circuit 63 latches, in responseto the activation of a matching signal HIT1 output from a judgmentcircuit 71, an address signal ADD, which is supplied via a throughsilicon via TSV. Besides the above circuits, a circuit block used forrow access may be referred to as a “row access circuit.” To the columndecoder 62, a column address CA is supplied via a column address latchcircuit 64. The column address latch circuit 64 latches, in response tothe activation of a matching signal HIT2 output from a judgment circuit72, an address signal ADD, which is supplied via a through silicon viaTSV. Besides the above circuits, a circuit block used for column accessmay be referred to as a “column access circuit.”

The judgment circuits 71 and 72 compare a chip address LADD0, which issupplied from the interface chip IF via the through silicon via TSV,with a unique chip addresses LID, which is assigned to the core chipsCC0 to CC7. When both match with each other, the matching signals HIT1and HIT2 are activated. A chip address LID is held by a chip addressholding circuit 65. The chip address holding circuits 65 are connectedin cascade among the core chips CC0 to CC7 via the through silicon viasTSV2 of a type shown in FIG. 2B. Accordingly, a different chip addressLID is set in each of the core chips CC0 to CC7.

Moreover, according to the present embodiment, judgment circuits 73 to77 are provided in the core chips CC0 to CC7. The judgment circuits 73to 77 compare chip addresses LID, which are held by the chip addressholding circuits 65, with chip addresses LADD1R, LADD2R, LADD1W, LADD2Wand LADD5, which are supplied from the interface chip IF via the throughsilicon vias TSV, respectively. When both match with each other,matching signals HIT3 to HIT7 are activated. Among the above matchingsignals, the matching signals HIT3 to HIT6 are supplied to a columnswitch control circuit 41 and a data amplifier control circuit 42 tocontrol operating timings of the column switch control circuit 41 andthe data amplifier control circuit 42. The matching signal HIT7 issupplied to the word driver 51, the sense circuit 53 and the like tocontrol a pre-charge timing of the memory cell array 50.

The above has described the basic circuit configuration of the corechips CC0 to CC7.

The following describes, as an example, the case where the PRA system isselected for an operation of the semiconductor device 10 according tothe present embodiment.

FIG. 13 is a timing chart illustrating a read operation.

In the example shown in FIG. 13, in synchronization with active edge −1of an external clock signal CK, an active command ACT is issued, and arow address RA is also input. The row address contains a chip addressLADD and a bank address BA. The command decoder 31 generates an activecontrol signal IACT in response to the active command ACT, and suppliesthe active control signal IACT to the latch circuit L10. The activecontrol signal IACT latched by the latch circuit L10 is supplied to eachof the core chips CC0 to CC7 via the through silicon vias TSV. The rowaddress is also supplied to each of the core chips CC0 to CC7. Asdescribed above, the row address contains the chip address and the bankaddress. Therefore, a bank specified by the bank address BA in a corechip specified by the chip address LADD becomes activated.

Then, in synchronization with active edge 0 of the external clock signalCK, a read command RD is issued, and a column address CA is also input.According to the PRA system, the column address contains a chip addressLADD and a bank address BA. The command decoder 31 generates a readcontrol signal R0 in response to the read command RD, and supplies theread control signal R0 to the latch circuit L11. The read control signalR0 latched by the latch circuit L11 is supplied to the read controlcircuit 100. The column address CA is also supplied to each of the corechips CC0 to CC7. The chip address LADD, which is contained in thecolumn address CA, is supplied to the read control circuit 100 via thelatch circuit L21.

As shown in FIG. 13, in the present example, the value of the additivelatency AL is seven. That is, the issuing timing of the read command RDcomes seven clock cycles ahead of the original timing, meaning that thecount values of the counter circuits 101 and 103 shown in FIG. 10 areset to seven. Therefore, the read control signal R0, which is generatedin response to the issuing of the read command RD, is delayed by sevenclock cycles, and then output as a read control signal R1 insynchronization with the internal clock signal ICLK. Moreover, in thepresent example, the count values of the counter circuits 102 and 104shown in FIG. 10 are set to two. When the burst length BL is set toeight, a read control signal R2 is activated two clock cycles after theactivation of the read control signal R1.

As indicated by reference symbol r1, the activation timing of the readcontrol signal R1 is in synchronization with the output timing of a chipaddress LADD1R. Therefore, to each of the core chips CC0 to CC7, thechip address LADD1R is supplied in synchronization with the read controlsignal R1. As a result, among the core chips CC0 to CC7, only thejudgment circuit 73 in a core chip specified by the chip address LADD1Ractivates the matching signal HIT3. In synchronization with theactivation of the matching signal HIT3, the column switch controlcircuit 41 activates a column switch 52, and outputs read data, whichare amplified by a sense amplifier, to a data bus DB. The data bus DB isa line connecting the column switch 52 to the data amplifier 70.

As a result, on the data bus DB, all read data pre-fetched from thememory cell array 50 appear. The data amplifier control circuit 42activated by the matching signal HIT3 activates the data amplifier 70corresponding to half of the read data, which are then output to theinterface chip IF via the through silicon vias TSV.

Moreover, as indicated by reference symbol r2, the activation timing ofthe read control signal R2 is in synchronization with the output timingof a chip address LADD2R. Therefore, to each of the core chips CC0 toCC7, the chip address LADD2R is supplied in synchronization with theread control signal R2. As a result, among the core chips CC0 to CC7,only the judgment circuit 74 in a core chip specified by the chipaddress LADD2R activates the matching signal HIT4. The data amplifiercontrol circuit 42 activated by the matching signal HIT4 activates thedata amplifier 70 corresponding to the remaining half of the read data,which are then output to the interface chip IF via the through siliconvias TSV.

The read data that are transferred in two stages as described above aresequentially converted into serial data by the parallel/serialconversion circuit 26 in the interface chip IF, and then transferred tothe FIFO circuit 27. The FIFO control circuit 28, which controls anoperation of the FIFO circuit 27, activates a timing signal FIFORS onceon the basis of the read control signal R1, thereby controlling theoutput timing of the first read data transferred. The FIFO controlcircuit 28 activates the timing signal FIFORS one more time on the basisof the read control signal R2, thereby controlling the output timing ofthe second read data transferred. As a result, from the datainput/output terminal 14, all the read data DQ are output in the form ofserial data. In the example shown in FIG. 13, the value of the CASlatency CL is eight. Accordingly, a process of outputting read datastarts 15 clock cycles (=AL+CL) after the read command RD is issued.

In that manner, the read control signal R0 is delayed in the interfacechip IF to generate the read control signals R1 and R2. Insynchronization with the read control signals R1 and R2, the chipaddresses LADD1R and LADD2R are each supplied to the core chips CC0 toCC7. Therefore, it is unnecessary to control latency in the core chipsCC to CC7. Thus, it is unnecessary to provide a latency counter or thelike in the core chips CC0 to CC7, as well as to supply the internalclock signal ICLK to the core chips CC0 to CC7 from the interface chipIF.

FIG. 14 is a timing chart illustrating a write operation.

In the example shown in FIG. 14, in synchronization with active edge −1of an external clock signal CK, an active command ACT is issued, and arow address RA is also input. Moreover, in synchronization with activeedge 0 of the external clock signal CK, a write command WR is issued,and a column address CA is also input.

As shown in FIG. 14, in the present example, the value of the additivelatency AL is seven, and the value of the CAS write latency CWL is six,meaning that the count value of the counter circuit 201 shown in FIG. 11is set to seven (=AL), and the count value of the counter circuit 202 isset to six (=CWL). Therefore, the write control signal W0 that isgenerated in response to the issuing of the write command WR is delayedby 13 clock cycles and then output as a write control signal W1 insynchronization with the internal clock signal ICLK. Moreover, in thepresent example, when the count values of the counter circuits 203 and206 shown in FIG. 11 are set to 2 and the burst length BL to eight, awrite control signal W2 is activated two clock cycles after the writecontrol signal W1 is activated.

As indicated by reference symbol w1, the activation timing of the writecontrol signal W1 is in synchronization with the output timing of a chipaddress LADD1W. Therefore, to each of the core chips CC0 to CC7, thechip address LADD1W is supplied in synchronization with the writecontrol signal W1. As a result, among the core chips CC0 to CC7, onlythe judgment circuit 75 in a core chip specified by the chip addressLADD1W activates the matching signal HIT5. In synchronization with theactivation of the matching signal HIT5, the data amplifier 70 isactivated, outputting 4-bit write data, which are the first half ofwrite data transferred from the interface chip IF in a parallel manner,to the data bus DB.

Moreover, as indicated by reference symbol w2, the activation timing ofthe write control signal W2 is in synchronization with the output timingof a chip address LADD2W. Therefore, to each of the core chips CC0 toCC7, the chip address LADD2W is supplied in synchronization with thewrite control signal W2. As a result, among the core chips CC0 to CC7,only the judgment circuit 76 in a core chip specified by the chipaddress LADD2W activates the matching signal HIT6. In synchronizationwith the activation of the matching signal HIT6, the data amplifier 70is activated, outputting 4-bit write data, which are the second half ofwrite data transferred from the interface chip IF in a parallel manner,to the data bus DB.

As a result, on the data bus DB, all write data transferred from theinterface chip IF appear. Then, in synchronization with the matchingsignal HIT6, the column switch control circuit 41 is activated, and thewrite data are written in a parallel manner into the memory cell array50.

In that manner, according to the present embodiment, even the latencycontrol needed for the write operation is performed inside the interfacechip IF. Therefore, as described above, it is unnecessary to provide alatency counter or the like in the core chips CC0 to CC7, as well as tosupply the internal clock signal ICLK to the core chips CC0 to CC7 fromthe interface chip IF.

FIG. 15 is a timing chart illustrating an auto-precharge operation.

What is shown in FIG. 15 is an example in which an auto-prechargeoperation takes place after a read operation. The read operation hasbeen described with reference to FIG. 13. In the example shown in FIG.15, after a lapse of four clock cycles from the read control signal R1is activated, a read auto-precharge signal RAP1 is activated, meaningthat the count value of the counter circuit 312 is set to four. Afterthat, in synchronization with the read/write clock signal ICLKRW, anyone of auto-precharge signals AP0 to AP7 specified by a bank address BAis activated and then supplied to the core chips CC0 to CC7.

As indicated by reference symbol apl, the activation timing of theauto-precharge signals AP0 to AP7 is in synchronization with the outputtiming of a chip address LADD5. Therefore, to each of the core chips CC0to CC7, the chip address LADD5 is supplied in synchronization with theauto-precharge signals AP0 to AP7. As a result, among the core chips CC0to CC7, only the judgment circuit 77 in a core chip specified by thechip address LADD5 activates the matching signal HIT7. As a result, thebanks specified by the auto-precharge signals AP0 to AP7 in the corechip are pre-charged.

In that manner, according to the present embodiment, even the delayoperation needed for the pre-charge operation is performed inside theinterface chip IF. Therefore, as described above, it is unnecessary toprovide a delay circuit or the like in the core chips CC0 to CC7, aswell as to supply the internal clock signal ICLK to the core chips CC0to CC7 from the interface chip IF.

It is apparent that the present invention is not limited to the aboveembodiments, but may be modified and changed without departing from thescope and spirit of the invention.

For example, according to the above embodiment, an operation of decodinga chip address LADD is performed in the core chips CC0 to CC7. However,an operation of decoding a chip address LADD may be performed inside theinterface chip IF. In this case, as shown in FIG. 16, a decoder 250 andcounter circuits 260 to 267, which become replicas, are provided; enablesignals EN0 to EN7, which are output from the counter circuits 260 to267, are supplied to the core chips CC0 to CC7. In this case, if theenable signals EN0 to EN7 are transferred to the core chips CC0 to CC7with the use of the through silicon vias TSV3 of a type shown in FIG.2C, it is unnecessary to provide a judgment circuit in the core chipsCC0 to CC7. Furthermore, as shown in FIG. 17, if commands C0 to C7 aregenerated by calculating the logical products of the enable signals EN0to EN7 and an internal control signal, and then transferred to the corechips CC0 to CC7 with the use of the through silicon vias TSV3 of a typeshown in FIG. 2C, it is possible to selectively supply a command only toa core chip that carries out a column operation.

Moreover, according to the above embodiment, the example in which thePRA system is selected has been described. However, the presentinvention can be applied to the case where the LRA system is selected.According to the LRA system, no chip address LADD is supplied when acolumn command is issued. However, a chip address LADD can be generatedfrom a bank address BA. For example, when the address assignment of theLRA-1 system shown in FIG. 4 is selected, it is possible to identify achip address LADD on the basis of a bank address BA that is suppliedwhen a column command is issued, because one core chip in each bank isactive. That is, as shown in FIG. 18, all that is required is asfollows: a chip address generation circuit 400 including a decoder 410,which decodes a bank address BA, and chip address holding circuits 420to 427, which hold a chip address for each bank, is provided in theinterface chip IF; a chip address LADD (ROW), which is specified when anactive command ACT is issued, is held by the chip address holdingcircuits 420 to 427 corresponding to a specified bank. Then, on thebasis of a bank address BA that is supplied when a column command isissued, the chip address is read out from the corresponding chip addressholding circuits 420 to 427. Therefore, even in the LRA system, it ispossible to acquire a chip address LADD (COLUMN) at a time when a columncommand is issued.

Moreover, according to the present invention, an output timing of aninternal control signal (which is for example a read control signal R1)that is delayed in the interface chip IF does not necessarily come atthe same time as an output timing of a corresponding chip address (whichis for example a chip address LADD1R). There can be a difference betweenthe output timings of the internal control signal and chip address, aslong as both are in synchronization with each other and thereforeassociated with each other when being processed in the core chips CC0 toCC7.

What is claimed is:
 1. A semiconductor device comprising, a first chipincluding a timing control circuit that outputs, in response to a firstcommand signal and a clock signal supplied from outside, a plurality ofsecond command signals having different timings from each other insynchronization with the clock signal; and a second chip stacked on thefirst chip including a plurality of internal circuits, each of theinternal circuits performing an operation indicated by the first commandsignal in synchronization with corresponding one of the second commandsignals, wherein the clock signal is not supplied from the first chip tothe second chip.
 2. The semiconductor device as claimed in claim 1,wherein the first chip includes a plurality of first through siliconvias penetrating the first chip, the second chip including a pluralityof second through silicon vias penetrating the second chip, and thesecond command signals being transferred from the first through siliconvias to the second through silicon vias, respectively.
 3. Asemiconductor device comprising, a first chip including a timing controlcircuit that outputs, in response to a first command signal and a clocksignal supplied from outside, a plurality of second command signalshaving different timings from each other in synchronization with theclock signal; and a second chip stacked on the first chip including aplurality of internal circuits, each of the internal circuits performingan operation indicated by the first command signal in synchronizationwith corresponding one of the second command signals, wherein the secondchip further includes a memory cell array and a data bus, the internalcircuits include a column switch which connects the memory cell arrayand the data bus based on an address signal, and a data amplifier whichamplifies data on the data bus, and each of the column switch and thedata amplifier is activated in synchronization with corresponding one ofthe second command signals.
 4. The semiconductor device as claimed inclaim 3, wherein the memory cell array performs a pre-charge operationin synchronization with one of the second command signals.
 5. Asemiconductor device comprising, a first chip including a timing controlcircuit that outputs, in response to a first command signal and a clocksignal supplied from outside, a plurality of second command signalshaving different timings from each other in synchronization with theclock signal; and a second chip stacked on the first chip including aplurality of internal circuits, each of the internal circuits performingan operation indicated by the first command signal in synchronizationwith corresponding one of the second command signals, wherein aplurality of the second chips are provided, the first chip commonlysupplies the second command signals to the second chips, the first chipcommonly supplies a first chip address identifying one of the secondchips to the second chips in synchronization with each of the secondcommand signals, and the internal circuits are activated when the firstchip address matches a second chip address assigned to each of thesecond chips.
 6. A semiconductor device comprising, a first chipincluding a timing control circuit that outputs, in response to a firstcommand signal and a clock signal supplied from outside, a plurality ofsecond command signals having different timings from each other insynchronization with the clock signal; and a second chip stacked on thefirst chip including a plurality of internal circuits, each of theinternal circuits performing an operation indicated by the first commandsignal in synchronization with corresponding one of the second commandsignals, wherein the first chip further includes a FIFO circuit thatoutputs read data supplied from the second chips to the outside inresponse to at least one of the second command signals.
 7. Asemiconductor device, comprising: an interface chip to which an addresssignal and a first command signal are supplied from outside; and aplurality of core chips to which different chip addresses are assigned,respectively, wherein the interface chip includes a first command delaycircuit generating a second command signal by delaying the first commandsignal, and a first chip address delay circuit generating a second chipaddress by delaying a first chip address, the interface chip commonlysupplying the second command signal and the second chip address to thecore chips, and each of the core chips includes a first judgment circuitactivating a first matching signal when the second chip address matchesa chip address assigned to the core chips, and a first internal circuitperforming an operation in synchronization with the second commandsignal when the first matching signal is activated.
 8. The semiconductordevice as claimed in claim 7, wherein each of the core chips furtherincludes a memory cell array, a row access circuit performing a rowaccess to the memory cell array, and a column access circuit performinga column access to the memory cell array, the first command signal isissued when the column access is to be performed, and the first internalcircuit is included in the column access circuit.
 9. The semiconductordevice as claimed in claim 8, wherein the interface chip furtherincludes a second command delay circuit generating a third commandsignal that is activated at a later timing than the second commandsignal by delaying one of the first and second command signal, and asecond chip address delay circuit generating a third chip address thatis activated at a later timing than the second chip address by delayingone of the first and second chip addresses, the interface chip commonlysupplying the third command signal and the third chip address to thecore chips, each of the core chips further includes a second judgmentcircuit activating a second matching signal when the third chip addressmatches a chip address assigned to the core chips, and a second internalcircuit performing an operation in synchronization with the thirdcommand signal when the second matching signal is activated, the firstinternal circuit includes at least one of a column switch and a dataamplifier included in the column access circuit, and the second internalcircuit includes at least other of the column switch and the dataamplifier included in the column access circuit.
 10. The semiconductordevice as claimed in claim 9, wherein each of the core chips activatesthe column switch in response to the second command signal and activatesthe data amplifier in response to the third command signal to outputread data read out from the memory cell array to the interface chip whenthe first command signal indicates a read operation.
 11. Thesemiconductor device as claimed in claim 9, wherein each of the corechips activates the data amplifier in response to the second commandsignal and activates the column switch in response to the third commandsignal to store write data supplied from the interface chip into thememory cell array when the first command signal indicates a writeoperation.
 12. The semiconductor device as claimed in claim 9, whereinthe interface chip further includes a third command delay circuitgenerating a fourth command signal by delaying any one of the first tothird command signals, and a third chip address delay circuit generatinga fourth chip address by delaying any one of the first to third chipaddresses, the interface chip commonly supplying the fourth commandsignal and the fourth chip address to the core chips, and each of thecore chips further includes a third judgment circuit activating a thirdmatching signal when the fourth chip address matches a chip addressassigned to the core chips, and a third internal circuit performing apre-charge operation of the memory cell array in synchronization withthe fourth command signal when the third matching signal is activated.13. The semiconductor device as claimed in claim 7, wherein the firstchip address is part of the address signal supplied from the outside insynchronization with the first command signal.
 14. The semiconductordevice as claimed in claim 7, wherein the interface chip furtherincludes a chip address generation circuit that generates the first chipaddress based on part of the address signal supplied from the outside insynchronization with the first command signal.
 15. The semiconductordevice as claimed in claim 14, wherein the chip address generationcircuit generates the first chip address based on a bank addressincluded in the address signal.
 16. The semiconductor device as claimedin claim 7, wherein the interface chip and the core chips are stacked oneach other, and are electrically connected together via through siliconvias provided at least in the core chips.
 17. The semiconductor deviceas claimed in claim 7, wherein the interface chip is supplied with anexternal clock signal from outside and further includes a clockgeneration circuit outputting an internal clock signal in response tothe external clock signal, and both the second command signal and thesecond chip address synchronize with the internal clock signal.
 18. Thesemiconductor device as claimed in claim 17, wherein each of the corechips is not supplied with the external clock signal and the internalclock signal.
 19. The semiconductor device as claimed in claim 7,wherein the interface chip further includes first and second throughsilicon vias, each of the core chips further includes third and fourththrough silicon vias respectively corresponding to the first and secondthrough silicon vias, the second command signal is transferred fromfirst through silicon via to each of the third through silicon vias, andthe second chip address is transferred from second through silicon viato each of the fourth through silicon vias.